Grinding pin



FIG. 1 illustrates a top front perspective view of a grinding pin;

FIG. 2 illustrates a top plan view of the pin of FIG. 1;

FIG. 3 illustrates a bottom plan view of the pin of FIG. 1;

FIG. 4 illustrates a front elevational view of the pin of FIG. 1 the rear elevational view being identical thereto; and,

FIG. 5 illustrates a side view of the pin of FIG. 1 the opposite side elevational view being identical thereto. 

The ornamental design for a grinding pin, as shown and described. 